Phil Kavanagh to Build Return Module

XAP will use an almost standard Kavanagh hot air balloon for the re-entry and controlled landing.   This will be the first controlled landing of a high stratosphere or mesosphere manned or un-manned balloon.  Historically upper stratosphere balloons have had uncontrolled descents because of the adiabatic lapse rate of the lifting gas in the balloon and the temperature gradient in the stratosphere.  Descent causes super heating of the gas. This can only be compensated for by releasing great amounts of gas.  When the balloon enters the troposphere the gas cools and the balloon drops out of control.  (It is impossible to carry enough ballast to compensate for this phenomenon, so normally the use of a parachute impact landing is the only ending for high flights.)

The flight procedure of XAP entails utilizing the Kavanagh hot air balloon as a "Tow balloon" for the initial phases of the ascent (to minimize the load on the balloon cluster in the dense lower regions of the troposphere) and to control the descent on return.  This is the only way a safe landing under control can be executed.

XAP is extremely proud that our first choice for provider of this essential component has accepted the commission and will be our partner in this great endeavor.